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These authors share their idea for getting around typical drawbacks that occur during the flame test such as short-lived colors that might not be very intense.

The factors influencing the site of attack of [ (phenylthio)(trimethylsilyl)methyl]lithium (1) with enones were investigated. Cyclohexenone (2) was chosen as a model compound, and conjugate addition occurred in THF-HMPA or DME; this mode of addition was also promoted by a potassium counterion. When the reaction was carried out with other enones, conjugate addition in THF-HMPA or DME was only observed if the P-position or the a,p-unsaturated ketone was not disubstituted. 1,4-Addition of 1 could be accomplished by preparation of the cuprate. The use of this approach was illustrated by a preparation of 4,4-dimethylcyclopent-2-en-l-one (28). For determination of the influence of DME on the regiochemical control of the addition of other sulfur-containing anions to enones, the study was extended to the anions derived from 1,3-dithian (29), bis(pheny1thio)methane (30), bis(phenylthio)(trimethylsilyi)methane (35), and bis(trimethylsilyl)(phenylthio)methane (36). With these anions, DME did not promote conjugate addition to any significant extent. (1) Parts of this work were carried out at the University of Southampton, for which an SRC postdoctoral fellowship is gratefully acknowledged, and the University 0 Rao, A. V. R.; Venkatawamy, G.; Javeed, M.; Deshpande, V. H.; Rao, B. R.

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